An early-stage AI company building the operating system for institutional investors is hiring its Founding Chief Technology Officer (CTO). This is a hands-on technical leadership role at the earliest stage. You'll work directly with the founder to architect and scale the core platform from the ground up. The platform combines modular workflow orchestration, an AI-powered domain assistant, and a deep document intelligence layer to replace fragmented, manual processes with structured intelligence. We sit at the intersection of AI and institutional finance, building for sophisticated, high-value clients in a category that almost no one is solving with serious AI infrastructure today. The CEO is an experienced operator with deep client-side fluency - a rare founder fit for a domain-specialised platform. Pre-seed funding closed; building toward Series A. Co-founder level structure available for the right person. What You'll Do Lead all technical strategy, architecture, and engineering execution Build and scale a small, high-quality engineering team Own the development of core capabilities: agentic workflow orchestration, document intelligence, LLM integration, and data pipelines Co-own product development with the CEO to translate client needs into product Stand alongside the CEO as technical co-founder - engaging clients, partners, and investors as the company scales Requirements Proven experience building and shipping software products end-to-end Production experience with AI/ML systems is required; experience with LLMs and AI-native product development essential Deep hands-on technical capability - you are willing to architect and code A commercial mindset: you understand how technology creates business value and can engage confidently with clients and partners A founder's mindset: you thrive with autonomy, ambiguity, and the opportunity to build something from scratch. You understand that an early-stage startup requires constant iteration, shipping, and testing to find product-market fit Prior startup or early-stage experience strongly preferred Experience with B2B products serving sophisticated enterprise buyers is a plus Direct exposure to institutional finance, asset management, or alternative investment workflows is a plus, not a requirement Benefits Founding team equity - co-founder level structure available for the right person Direct influence over company direction and engineering culture from day one The chance to build a category-defining company at the intersection of AI and institutional finance Hands-on technical role with full ownership of the stack - you are not inheriting a roadmap Hybrid working: London-based, 1-2 days per week in office; open to elsewhere in Europe for the right person